Reader System identifies and tracks multiple RFID tags.

Press Release Summary:

With positioning accuracy to 0.5 m for each transponder, RFID-radar based readers simultaneously identify, locate, and track multiple RFID tags in 100 m zone. Single measurement point allows mobile operation as well as ability to perform 2D and 3D location of all transponders in zone with pointing accuracy of vector as accurate as 1° for each transponder. Products use 10 kHz of radio spectrum, and 2 RFID-radar systems can operate within 4 m of each other.

Original Press Release:

Trolley Scan (South Africa) Invents RFID-Radar

Trolley Scan (Pty) Ltd, a Johannesburg,South Africa based developer of RFID (Radio Frequency Identification) technologies announced the development of an amazing new RFID technology that they have trademarked "RFID-radar". In the past RFID readers were limited to identify tags that were in the reader zone. Based around a major discovery made by Trolley Scan, RFID-radar based readers will now be able to identify, locate and track those same multiple tags in the reader zone.

Said Mike Marsh, Managing Director of Trolley Scan -"The breakthrough with RFID-radar is the ability to measure the distance travelled by a signal from a transponder to a reader accurately, over long distances, using minimal radio spectrum to minimise effects on other users, and with very low cost transponders and readers. This measurement allows us to identify, locate accurately and track the movement of tens of transponders in front of a reader at the same time.

In older generation RFID systems, operating ranges were a few centimeters, so location information was not important as the transponder was always close to the reader. In modern systems we have increased the operating range to tens of meters and will soon reach the one hundred meter range mark with passive tags. Here location information together with the identity information becomes essential as so many transponders can be located in such a large area."

Said Marsh- "In the past it was not possible to measure the range of a transponder from a reader. The practicalities of UHF RFID mean that traditional approaches such as signal strength variation cannot be applied for range measurements. Our newly invented technique allows us to measure the range of a transponder to an accuracy of 0,5 meters and a pointing direction of just 1 degree, for transponders as far away as 100 meters, with up to 100 transponders in the zone at a time. This development is revolutionary, in that instead of needing expensive transponders and readers, our development allows this technique to be applied to the "US$five cent" transponder and the "US$100" reader. We make the measurements from a single reader site, making the equipment suitable for use in mobile applications such as when the reader is fitted to a forklift truck."

The new technology will result in the development of an entire new set of applications for computer based equipment. Applicatiions could include the location of goods in a warehouse; tracking of individual animals in a herd; the monitoring of the movement of assets in a building; the location of parcels and airline luggage in a warehouse; the monitoring of children in a creche; or the monitoring of security zones to ensure secure areas are avoided.

The impact of RFID-radar technology on the future generations of RFID systems is going to be significant. Already more than 100 companies from all over the globe have contacted Trolley Scan about getting prototypes, commercial versions or OEM modules for incorporating into their own products.

In the future there will be RFID readers that just give identity information, and there will be RFID-radar type readers that give identity, location and tracking information.

Photos of the RFID-radar and the test installation can be seen at

About Trolley Scan (Pty) Ltd
Trolley Scan have proven to be a major creative force in the development of UHF RFID technologies. Founded in 1995, the staff of Trolley Scan have a pedigree that goes back to 1990 when the first low cost RFID protocol was developed by the founder while working for a South African government research organisation, culminating in 1994 in the demonstration of a supermarket trolley containing 38 items being scanned automatically in a supermarket in Pretoria. In 1998, the founders of Trolley Scan developed an entirely new set of protocols for UHF RFID which they have been actively promoting. They also have addressed the situation of the 3 dimensional scanning of goods, and have developed a very low power RFID version which they commercialise under the EcoTag trademark. In August 2005 Trolley Scan invented RFID-radar. Trolley Scan are based in Johannesburg South Africa.

Trolley Scan licence their patents and technology to companies around the world who wish to produce this technology. Trolley Scan sell RFID systems to users in 44 countries. Complete systems can be ordered via their website.

RFID systems comprise of a transponder that is attached to the goods to be identified and a reader that converts the information in those transponders to a computer compatible format for processing. The transponder can comprise of a simple antenna and a small integrated circuit that can be produced at low cost. Operating in the 860 to 960 MHz (UHF) band, the transponder can be identified meters away from the reader, can be identified in a group with up to 1000 other transponders when being read, and can be identified very quickly. In view of the system using radio waves for energy and information transfer, it is not necessary for the transponder and reader to be in line of sight.

Potential use of these systems is extensive, from herd animal tracking, library books, pallets, warehousing, bank and postal bags, asset tracking, airline luggage, vehicle monitoring (access and parking), to intelligent buildings (tracking files, documents and assets moving around an office to minimise finding time).

The ultimate goal is to use these transponders with their inbuilt anti-shoplifting features to replace the barcodes labelling goods in a retail store allowing filled supermarket trolleys to be scanned in seconds in unmanned self service checkout aisles.

RFID-radar is a new development that includes a measurement of range from the reader to the transponder. This measurement is made repeatedly allowing the reader to report range and tracking information for all transponders in the zone. The major development comes from the ability to measure the range accurately from a single reader position. This single measurement point allows mobile operation, as well as 2D and 3D location information of all transponders in the zone. The measurement of range is a major breakthrough, as the radio signals travel at 300 000 kilometers/second and the timing accuracy measurements are limited to 1/10000th of a second. The RFID-radar has to operate in the very limited radio spectrum shared with the many users who use radio devices, such as cell phones. RFID-radar uses just 10kHz of radio spectrum and is so enviromentally friendly that two RFID-radar systems can operate within 4 meters of each other. The RFID-radar delivers positioning accuracy of each transponder in the zome to 0.5 meters with a maximum range of 100 meters. The pointing accuracy of a vector for locating in 2D and 3D can be as accurate as 1 degree for each transponder.

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